Pneumatic action for interior piano-players.



M. CLARK.

, PNEUMATIC ACTION FOR INTERIOR PIANO PLAYERS.

APPLlcATloN FILED JULY 28.1915.

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UNITED g sTATEs PATENT oEErcE MELVILLE CLARK, OF CHICAGO, ILLINOIS, ASSIGNOR TO MELVILLE CLARK PIANO COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PNEUMATIC ACTION FOR INTERIOR PIANO-PLAYERS.

1,160,260. Specicaton of Letters Patent.

Patented Nov. 16, 1915. Application led July 28, 1915. Serial N o. 42,269.

To all whom z't may concern Be it' known that I, MELvrLLE CLARK, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Pneumatic Actions for Interior Piano-Players, of which the following is a. specification, reference beinghad to the accompanying drawings, forming a part thereof. v

The purpose of this invention is to provide an improved construction of the pneumatic action of an automatic player in an upright piano.

It consists in the elements and features of construction shown and described as indicated in the claims.

In the drawings Figure 1 isa fore-andaft vertical section of a portion of an upright piano equipped with a pneumatic action embodying this invention.v

The structure embodying this invention is designed as a player action for playing solo and accompaniment having two sets of pneumatics for each of the keys of the piano which are to be included inthe range of playing both solo and accompaniment. The structure therefore comprises the two primary pneumatic chambers, 1 and 2, which are completely separated by a vertical partition, 3, and which communicate with suitable means, not shown, for producing partial vacuum therein. The front ywall of the forward chamber, 1, and the rear wall of the rear chamber, 2, constitute the duct boards having the ducts, 4 and 5, which lead from the primary pneumatics, 6 and 7, in said chambers respectively for connection with their respective motor pneumatics, and having the valve chambers, 8 and 9, communicating with the atmosphere and with the primary pneumatic chambers, and in which are situated the valves, 11, connected with and actuated by the primary pneumatics respectively in the perfectly familiar manner.

The specific purpose of the invention is to obtain as compact an arrangement as possible of two sets of motor pneumatics both of which shall be positioned horizontally, the corresponding pneumatics of the two sets being connected for acting upon the hammer action for playing the same note, but one of said pneumatics being connected for striking the note 'more forcibly vand playing more loudly than the other. The space available for the two sets of motor pneumatics in fore-and-aft direction being quite limited, it becomes necessary to utilize as great a portion of it as possible for the length of the two pneumatics, and therefore to locate the least possible amount of the necessary supporting and communicating structure in this space either between or beyond the front and rear end of the pneumatics. For this purpose the construction shown is designed so as to have positioned between the two sets of pneumatics only the duct'board through which they must be supplied with air connections, and utilizing this duct board as the physical means of supporting both sets of pneumatics. To this end there is provided under the primary pneumatic chambers a horizontal duct board, .12, whose ducts 12, at the rear end are continuous with the ducts in the rear wall of the rear primary pneumatic cham- The ducts, 4, open at their lower ends through the forward wall of the forward primary pneumatic chamber, 1. A vertical duct board, 15, is provided having two sets of ducts therein, the rear set of ducts, 16, opening rearwardly through the rear surface of said vertical duct board for registering with the forward ends of the ducts, 12, in the horizontal duct board, 12, and the forward set, 17, of said vertical duct board opening rearwardly above the openings of the rear set for registering with the opening, 4, of the ducts, 4, in the forward wall of the primary pneumatic chamber, 1. Said duct board is rigidly joined to the unitary structure which comprises the primary pneumatic chambers and the horizontal duct board, 12, by lapping the upper end of said vertical duct board, 15, onto the forward side on said unitary structure with the duct apertures registered respectively as above described, permanent air-tight junctions being secured at such lap in a well understood manner, and the entire structure comprising said primary pneumatic chambers, horizontal duct board at the bottom and vertical duct board, 15, is made rigid by suitable stiffening brackets, 15, positioned in the angle between the forward side of the forward primary pneumatic chamber, 1, and the upper end of the vertical duct board or by any other convenient mechanical means.

The motor pneumatics of both the front set 18, and the rear set 19, are mounted in three tiers in staggered arrangement according to the familiar method so as to obtain adequate lateral extent for each pneumatic. per tier of the rear set of motor pneumatics is mounted upon the lower side of the hori- Zontal duct board, 12. For mounting the other two tiers of said rear set rearwardly projecting horizontal shelves, 20, 20, are provided extending rigidly from the vertical duct board, 15; and for mounting the pneumatics, 18, of the forward set, there are provided forwardly extending rigidly mounted shelves, 21. rlhe motor pneumatics of the rear set have their moving walls below for collapsing upward, and those of the forward set have their moving walls above for collapsing downward; that is to say, the rear set of pneumatics are mounted below their supports and the forward set are mounted above their supports, respectively. The motor pneumatics obtain communication with their respective ducts, 16 and 17, in the vertical duct board, 15, through proper ducts, 20a, and 21a, in the supporting shelves, 20 and 21, respectively, the upper tier of the rear pneumatics, however, communicating directly with the horizontal ducts, 12a, in the duct board, 12, upon which said upper tier of pneumatics are mounted. From the rear side at the lower end of the vertical duct board, 1.5, a rib or bracket, 24, projects rearwardly and from its rear end there is projected downward a fulcrum-supporting bar, 25, whose lower edge is notched to receive levers, 26, which are thus fulcrumed by means of a suitable pivot rod, 27, upon the lower end of said depending bar for vertical oscillation. Said levers extend forward under the forward set of motor pneumatics, 18, Vand their forward ends are connected respectively with the moving walls of said pneumatics in the familiar manner by means of the pitman rods, 28. The rear ends of said levers extend beyond therear ends of the motor pneumatics of the rear set, 19, and terminate for engagement under abutments, 80, upon the abstracts, 31, of the piano hammer action, so as to lift the aL- stracts by the downward collapse of the motor pneumatics, 18. The moving members of the motor pneumatics, 19, of the rear set are provided with terminals, 29, for connection of pitman rods, 32, which extend up behind the said rear set of motor pneumatics and all obtain guidance in the rear end portion, 12b, of the horizontal duct board, 12, which is projected rearward beyond the primary pneumatic chambers for this purpose; and above said guides, pitmen are provided with terminals, 33, for engagement under abutments, 84;, upon the abstracts, 31.

It will benoticed that the levers,26, are fulcrumed at such points between their ends that the longer arm of each which receives the action of the motor pneumatics,

v18, Iis about twice the length of the shorter arinwhich acts upon the abstracts. This permits the employment of motor pneumat- Vics,18, havinga depth of collapse and expansion twice as great as the stroke to be given the abstracts, and thereby causes the stroke thus'given with any given degree of partial vacuum in the primary pneumatic chamber, 1, to be substantially twice as powerful as it would be if the moving member of the motor pneumatics operated directly upon theabstract. And it will be noticed therefore that the motor pneumatics Vof the rear set whose moving walls do act directly upon the abstract and cannot utilize more vthan half as great a depth of expansion and collapse as theV notor pneumatics of the forward set, will strike onlv about half as forcibly as the said motor pneumatics of the forward set with the same degree of partial vacuum in the two primary pneumatic chambers. This construction, therefore. makes it possible to play different notes with different degrees of loudness while exhausting the two primary pneumatic chambers by the same exhaust devices and to the saine degree. However, I do not limit the present invention in thatV respect, and on the contrary the primary pneumatic chambers may be exhausted by different means and to different degrees without departing` from the substance of this invention, which consists in the structure described for obtaining compactness in the disposing of the two sets of pneumatics and adapting them to act with different force upon the hammer action.

1. In' combination with the hammer action of an upright piano, a pneumatic player action comprising two adjacent primary pneumatic chambers. the front wall of one and the rear wall of the other constituting duct boards; a fore-and-aft duct board extending under such chambers having its ducts continuous with the ducts of said rear wall; a vertical duct board situated approximately in the plane of said front wall having two sets of ducts connecting at their upper ends with the ducts of said front wall and said fore-and-aft board respectively; two sets of motor pneumatics mounted respectively behind and in front of said vertical duct board and communicating respectively with said two sets of ductstherein; the front set having` their moving walls above for collapsing downward, and the rear set having their moving walls below for collapsing upward; a set of fore-andaft levers fulcrumed below said motor pneumatics operatively connected at their forward ends with the front set of motor pneumatics; themovin'gl walls of the rear setfof motorvpneumatics having terminals for en'- gagement in the vertical fore-and-aft planes of the rear terminals of said levers respectively, the abstracts of said piano hammer action having each two abutments positioned for engagement respectively by the rear ends of the levers and said rear motor pneumatic terminals.

2. In combination with the hammer action of an upright piano, a pneumatic player action comprising two primary pneumatic chambers, a vertical duct board having two sets of ducts communicating respectively with the primary pneumatics in said two primary chambers, two sets of motor pneumatics mounted respectively in front of and behind said vertical duct board and communicating with the two sets of ducts respectively therein, a set of fore-and-aft eX- tending levers under said two sets of motor pneumatics, and a fulcrum support for said levers mounted upon said vertical duct board, the motor pneumatics of the forward set having their moving walls above for collapsing downward, and those of the rear set having their moving walls below for collapsing upward, and having terminals positioned respectively in the vertical foreand-aft planes of the rear terminals of said levers, the abstracts of the piano hammer action having each two abutments positioned for engagement respectively with said rear pneumatic terminals and the rear terminals of said levers.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois, this 10th day of July, 1915.

v MELVILLE CLARK.

VVitnes'ses:

EDNA M. MACINTOSH, LUCY I. STONE.

copies of this patent may be obtained for iive cents each, by addressing the Commissioner of Patents, Washington, D. C. 

